You can't go wrong with the West Side For Skinny Bastards programs.
Other then that just make sure your eating 5-6 meals a day, each containing a good protien source and stay away from junk food. Also make sure your are eating alot, I mean you shouldnt put down the fork until you are stuffed.
Make sure you have some good carbs/protien (i.e. Surge) before and after training as well.